Holographic recording medium and holographic recording and reproducing method
AssigneeTDK Corporation
InventorsTetsuro Mizushima, Takuya Tsukagoshi, Hideaki Miura, Jiro Yoshinari
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Abstract
A white-light reconstruction hologram and a Fourier hologram for data can be recorded in a same holographic recording medium. The holographic recording medium includes, in a substantially identical plane, a white-light reconstruction holographic recording layer region capable of forming a white-light reconstruction hologram, having a thickness of 2 μm to 80 μm, and a Fourier holographic recording layer region capable of multiplexed hologram recording, having a thickness of 100 μm to 2 cm.
Claims8
A holographic recording medium comprising, in a substantially identical plane,
- a single recording layer comprising a holographic recording material sandwiched from both sides by two substrates having an uneven shape including a step in thickness;
- and
- the single recording layer having a white-light reconstruction holographic recording layer region and a Fourier holographic recording layer region,
- the white-light reconstruction holographic recording layer region being capable of forming a white-light reconstruction hologram and having a thickness of 2 μm to 80 μm,
- the Fourier holographic recording layer region being capable of multiplexed hologram recording and having a thickness of 100 μm to 2 cm, and
- the thickness of each of the white-light reconstruction holographic recording layer region and Fourier holographic recording layer region being changed by the step height of the two substrates.
A holographic recording medium comprising, in a substantially identical plane,
- a single recording layer comprising a holographic recording material sandwiched from both sides by two substrates having an uneven shape including a step in thickness;
- and
- the single recording layer having a white-light reconstruction holographic recording layer region and a Fourier holographic recording layer region,
- the white-light reconstruction holographic recording layer region having a thickness of 2 μm to 80 μm and a white-light reconstruction hologram being formed in at least a part of the white-light reconstruction holographic recording layer region,
- the Fourier holographic recording layer region having a thickness of 100 μm to 2 cm and multiplexed holograms being recorded in at least a part of the Fourier holographic recording layer region, and
- the thickness of each of the white-light reconstruction holographic recording layer region and Fourier holographic recording layer region being changed by the step height of the two substrates.
A method of holographic recording comprising the step of irradiating, as an object beam, a two-dimensional pattern image created by a spatial light modulator to a white-light reconstruction holographic recording layer region in a holographic recording medium comprising, in a substantially identical plane, the white-light reconstruction holographic recording layer region capable of forming a white-light reconstruction hologram, having a thickness of 2 μm to 80 μm, and a Fourier holographic recording layer region capable of multiplexed hologram recording, having a thickness of 100 μm to 2 cm, the object beam is modulated by the spatial light modulator, is switched to an optical path different from an optical path used for irradiating the two-dimensional pattern image, is Fourier-transformed, and then is irradiated as an information beam to the Fourier holographic recording layer region in the holographic recording medium.
Dependencies are inferred from the claim text.